An adhesive pad according to a related art has a low adhesive strength and a low adhesion switching ratio at adhesion or removal. Also, applying a load to a bearing element in advance to increase a stiffness of an object, to fill a gap or to prevent abrasion is referred to as “pre-load.” Generally, due to a pre-load applied when the adhesive pad is used, there was a limitation in practical industrial applications. In particular, in a semiconductor industry, to transfer a nanostructure to a desired substrate, there is a technical need to minimize a pre-load for adhesion, a high adhesion switching ratio, and a change in adhesive properties of a smart adhesive pad on demand.
FIG. 1 illustrates an adhesive pad according to a related art. Referring to FIG. 1, the adhesive pad is formed by attaching a release paper onto a bottom surface of a hot melt adhesive (HMA) that is supplied in a form of a fabric from an extruder and simultaneously by coating a top surface of the HMA with a protective film. A pressing operation is performed by supplying the release paper and the protective film adhering to the HMA using a press. In the pressing operation, the HMA to which the release paper and the protective film adhere is cut into a predetermined shape using a cutting and creasing die, to manufacture the adhesive pad of FIG. 1.
The adhesive pad includes the protective film and the HMA on the release paper. An adhesive material of the HMA includes an epoxy-based hot melt material that may be hardened at a high temperature, has a stickiness to stick to an operator's hand, peripheral parts, and the like, and is provided in a form of a sheet with a release paper attached to one side.
To attach or detach the adhesive pad of FIG. 1 to or from a desired portion, a high pre-load is required.
However, due to the above issues, the adhesive pad has a limitation in practical industrial applications. In particular, in a semiconductor industry, to transfer a nanostructure to a desired substrate, it is important to minimize a pre-load applied for adhesion, a high adhesion switching ratio, and a change in adhesive properties of a smart adhesive pad on demand.